Pierce's design was later improved by U.S. appliance engineers Ivar Jepson, Ludvik Koci, and Eric Bylund of Sunbeam in the late 1930s. They altered the heating chamber and eliminated the recessed well which was hard to clean. They also made several improvements to the filtering mechanism. Their improved design of plated metals, styled by industrial designer Alfonso Iannelli, became the famous Sunbeam Coffeemaster line of automated vacuum coffee makers (Models C-20, C-30, C40, and C-50). The Coffeemaster vacuum brewer was sold in large numbers in the United States during the years immediately following World War I.
The Bunn 13300.0013 VP17-3BLK3L Pourover commercial Coffee Brewer The Bunn 13300.0013 VP17-3BLK3L Pourover commercial Coffee Brewer with Three Lower Warmers in Black is perfect for convenience stores family restaurants cafes or diners. Totally portable it can be used anywhere there's a plug. Just pour cold water in the top and coffee brews immediately up to 3.8 gal. per ...  More + Product Details Close
Other coffee brewing devices became popular throughout the nineteenth century, including various machines using the vacuum principle. The Napier Vacuum Machine, invented in 1840, was an early example of this type. While generally too complex for everyday use, vacuum devices were prized for producing a clear brew, and were popular up until the middle of the twentieth century.
This testing was designed to highlight the difference in how each machine extracted its coffee grounds. Remember, extraction is tied to water temperature, how long the grounds had to steep, and how evenly that water is distributed in the brew basket. (Depending on how the machine distributes the water and the shape of the basket, any particular ground may or may not receive the same amount of time in contact with water — thus any individual grind may be over-extracted, under-extracted, or just right.) Properly extracted grounds would have a balance of notes and aromas, from slight hints of acid to a pleasant amount of bitterness.
For many of us, the daily grind can't begin until we've had that first cup of piping hot coffee—so the right brewer is at the top of the list. The most basic coffee makers make at least a decent cup, but a little more money buys conveniences such as programmability, a thermal carafe to keep coffee hot longer, settings that let you adjust brew strength, and more.